First paragraph (this article has no abstract)

With interest we read the article by Castro and colleagues exploring the relationship
between sunlight exposure and ICU mortality [1]. Interestingly, less daylight exposure prior to ICU admission was associated with
a reduction in ICU mortality. While the authors mention the influence of light on
the development of delirium, it is also recognized that delirium is an independent
risk factor for death [2-4]. However, the authors did not adjust for delirium.